How to Choose Sustainable TPEs and Masterbatches: A Procurement Checklist

I've been managing materials procurement for a mid-sized manufacturer for about six years now. When we started looking into sustainable thermoplastic elastomers (TPEs) and masterbatches, I made every mistake in the book—including assuming that's sustainable meant 'just use recycled content.' After comparing quotes, auditing my own spending (roughly $180,000 across six years on specialty materials), and talking to more suppliers than I care to count, I've put together a checklist that actually works. If you're evaluating Avient or any other supplier for TPEs, colorants, or masterbatches, this is the exact process I use.

Who This Checklist Is For

This is for procurement managers and R&D folks who are being asked to find 'sustainable' materials but still have to hit a budget. It also applies if you're trying to answer specific technical questions like is silicone thermoplastic or thermoset, or if you're sourcing materials for something like plastic planters where both durability and environmental claims matter.

There are five steps. Step 3 is the one most people skip, and it's usually the reason a 'cheaper' material ends up costing more.

Step 1: Separate Material Fact From Marketing

The first thing I do is ask the supplier to state, in writing, what the material actually is. This matters more than you'd think. For example, a lot of people assume silicone is a thermoplastic—it's not. Most commercial silicone is a thermoset, which means it can't be re-melted and reprocessed the way a true thermoplastic can. That has huge implications for recyclability and, therefore, sustainability claims.

When I was looking at materials for a client's line of plastic planters, one supplier pitched a '100% recyclable silicone alternative.' That claim was technically true, but the material was a thermoset, so recycling it required a specialized chemical process that cost three times as much as mechanical recycling. The total carbon footprint was arguably worse than the standard TPE we were already using.

So, the check here is simple: get the material data sheet (MDS) and ask the supplier to classify the material explicitly. Is it a thermoset or a thermoplastic? If they can't answer that without a long pause, I move on.

Step 2: Look at the Backbone, Not the Brochure

Let's talk about TPEs specifically. A TPE is a family of materials, not a single material. The sustainability profile of a TPE depends entirely on its chemistry. For example, a TPE based on PP (polypropylene) is more easily recycled in an existing polyolefin stream than a TPE based on a specialty polymer like TPU.

Avient is a solid supplier here because they have a broad portfolio, but you need to make sure the specific grade you're being quoted actually aligns with your sustainability goals. I remember comparing two quotes for a project that required a soft-touch surface for a consumer product. The cheaper option was a standard TPE with a good price per pound. The better option, from a sustainability standpoint, was a pre-colored, recyclable TPE that cost more upfront but eliminated a secondary painting operation. The pre-colored option was the better TCO in the end, but I had to dig into the material specs to see why.

The check: Ask if the TPE is compatible with your existing recycling streams or if it requires a separate, niche recycling process. The answer will directly affect your end-of-life costs.

Step 3: Calculate the True Cost of Colorants (Including Masterbatch)

This is the step everyone forgets. You're not just buying a material; you're buying the color. And the way you buy color—whether it's a custom Avient colorant, a standard masterbatch, or a dry pigment—changes your manufacturing efficiency and your waste percentage.

I watched this play out when comparing quotes for an Avient masterbatch versus a cheaper generic colorant from a regional supplier. The generic colorant was $0.40 less per pound. But it required a higher let-down ratio (meaning we had to use more of it to get the same opacity), and it didn't disperse as well in our TPE base. We ended up with slightly streaky parts, and I rejected about 8% of the production run. That 8% waste wiped out my cost savings entirely—and then some.

When you compare colorant quotes, you are comparing a system, not a single price. You need the recommended let-down ratio and the dispersion spec in hand before you do any math.

Here's the checklist item: ask for trial pellets. Run them through your own injection molding or extrusion line. Don't rely on the supplier's lab data. I now have a standing policy that no colorant gets approved without a 50-pound trial run in-house first. It's a $200 cost that saves me from making a $5,000 mistake.

Step 4: Verify the Sustainability Claim (Don't Trust the Press Release)

When a supplier says 'sustainable,' that's an adjective, not a measurement. I specifically look for companies that back up the claim with data—ideally a third-party LCA (Life Cycle Assessment) or at minimum a detailed sustainability report that shows where the material comes from. I've mentioned before that Avient publishes a sustainability report, which is more than many of their competitors do. But a report in a PDF isn't the same as a verified eco-label.

For plastic planters, the end user might care if the material is UV-stable and won't crack. For the planet, you need to know if the material is mechanically recyclable, chemically recyclable, or biodegradable. These are three entirely different end-of-life scenarios, and they have different costs associated with them.

During a project last year (Q2 2024), we were comparing a 'bio-based' TPE against a recycled-content TPE. The bio-based one was made significantly greener—energy-intensive fermentation. But the recycled-content TPE was over 40% cheaper and had a lower carbon footprint because it was using post-industrial waste that could be mechanically recycled again. The numbers said one thing, but my gut initially told me 'bio-based' was the responsible choice. That was a classic gut-vs-data conflict.

Step 5: Build a TCO Budget, Not a Unit-Price Budget

If you take one thing from this guide, it's this: stop comparing price per pound. It is the most misleading metric in materials purchasing.

Here's a real comparison from my tracking spreadsheet:

• Vendor A: TPE at $2.10/lb, standard lead time, free color matching, but colorant sold separately at a premium.
• Vendor B: TPE at $2.35/lb, pre-colored, includes a specific masterbatch, slightly longer lead time.

Vendor A looks cheaper. But when I calculated the total cost per part, including the colorant let-down ratio, the energy required for the extra mixing step, and the rejected parts from inconsistency, Vendor A was actually 9% more expensive than Vendor B on a per-part basis. That's the kind of difference you can't see on a quote sheet.

To do this properly, create a spreadsheet with these columns: material cost per part, colorant cost per part, processing time per part (as cost), scrap rate percentage, and disposal cost. If you are comparing a thermoset like standard silicone against a thermoplastic like a TPE, you also need to account for scrap recycling. Thermoset scrap is landfill material in most cases; TPE scrap might be regrindable. (That's a huge reason why sustainable thermoplastic elastomers are gaining ground—the waste is worth something.)

Common Pitfalls I Still See

I've been doing this for years, and I still see the same three mistakes:

1. Ignoring the colorant interaction. A beautiful colorant in a spec sheet can fail when mixed with a different TPE base. You need to test the actual combination, not the individual components. This was the root cause of my 8% scrap rate.
2. Assuming all TPEs are recyclable. They are not. Some TPEs are thermoset-like in their behavior or designed to bond with materials that contaminate recycling streams. Always ask for the recycling category code.
3. Treating a sustainability report as a technical spec. A report like Avient's is useful for due diligence, but it doesn't tell you if a specific grade passes your UV test or flexural modulus requirements. I once picked a material based on its bio-content claims, only to fail our heat aging test. The bio-content was real, but it compromised the thermal stability we needed.

Also, regarding the plastic planters application—remember that outdoor applications require UV stabilizers. If you buy a generic TPE to save money, you might need to add UV protection separately, which increases your TCO. A supplier like Avient has pre-formulated outdoor grades that include UV stabilization, which can actually be cheaper when you factor in the additive cost.

Final Thought: The Data Isn't Just in the Quote

The most frustrating part of materials procurement is how much of the real cost is invisible at the quotation stage. You'd think a written quote would be complete, but it never is. It's only when you factor in time, waste, and hidden compatibility issues that the true picture emerges. I've made my share of bad calls by chasing a low number on a spreadsheet. Now, I use this checklist. It's not glamorous, but it saves me from the kind of mistake that ends with a warehouse full of unusable parts.

If you're still asking whether silicone is a thermoplastic or a thermoset, you can just look it up. But if you're trying to decide which sustainable thermoplastic elastomer is right for your budget, you're going to need more than a datasheet. You're going to need a process.